Tuesday, April 21, 2009

Tech Tip Tuesday

When you've finished glassing the outside of the canoe, you need to be able to finish the inside of the canoe. To do this, you lift the canoe off of the forms that the canoe was built on. A couple of important points here:
  • Before trying to remove the boat from the forms, check for any areas that may be problems - glue, that forgotten staple or broken fastener. They will cause problems.
  • If you didn't do a good job of taping the forms or have torn the tape, you may have bonded the hull to the forms - be careful!
  • If your boat has tumblehome, you need to be remove the forms from the strongback and twist them to remove them.
  • Have a helper or two when you do this - you'll need it.
  • Have somewhere to put the canoe when it's off the forms.
Ideally, before you bonded the bottom panels of the football together, you did a preliminary sanding on the (nearly) flat panels. (See this post and this post...) It's easier to do before the boat is assembled. Trust me.

Now that you've gotten the canoe off the forms, you need to be able to hold it right side up. There are three good ways that I've used and like - some better than others. The most universal method is the carpet cradle. They're basically a saw-horse of sorts, but instead of having a horizontal member across the top, you've got a strip of carpet set up like a hammock for your canoe. In the picture below, we've raised them up (On some, well, I'm not sure what they are, but they were in our barn...) to get a better working height. The only thing I don't like about the carpet cradles is that it swings a bit. Not bad, but not ideal.

Another pretty low-cost way is to use the foam kayak blocks taped to some sawhorses. The nice part is that you can re-use these blocks for transporting a boat. This is a decent solution and requires a minimum of materials.The last method that I'll suggest is to take your forms that are about a third of the way in from either end of the canoe and trace them onto some plywood scrap. Make sure they are short - only about 1/2 to 2/3 of the height of the full form. Use sections of foam pipe insulation to pad the plywood as shown. The cradles are mounted to the strongback with some pieces of 2-by. This arrangement works well. On this particular day, my student was trying out the fabric cradles - she'd been working on the cradle below the week before.

All of the methods allow you to roll the boat towards you to work sanding and scraping the inside. The best, in my opinion are the second and third as they aren't moving around as you're trying to work.

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